Broadcasting packets using network coding via sidelink with feedback

ABSTRACT

Methods, systems, and devices for wireless communications are described. A transmitter may identify a set of one or more packets for broadcast to a set of one or more user equipments (UEs) and transmit a set of one or more network encoded packets based on the set of one or more packets. The UEs may each rebroadcast one or more successfully received network encoded packets via sidelink communications. Each UE may report to the original transmitter via feedback indicating the one or more successfully received packets at each UE. The transmitter may generate an updated set of one or more network encoded packets based on the feedback from the UEs. The transmitter may continue to update and transmit the updated set of one or more network encoded packets based on feedback until the transmitter determines that each UE has recovered the set of one or more packets.

CROSS REFERENCE

The present Application for Patent claims the benefit of U.S.Provisional Patent Application No. 63/050,081 by Zhou et al., entitled“BROADCASTING PACKETS USING NETWORK CODING VIA SIDELINK WITH FEEDBACK,”filed Jul. 9, 2020, assigned to the assignee hereof, and expresslyincorporated by reference herein.

FIELD OF TECHNOLOGY

The following relates generally to wireless communications and morespecifically to broadcasting packets using network coding via sidelinkwith feedback.

BACKGROUND

Wireless communications systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be capable ofsupporting communication with multiple users by sharing the availablesystem resources (e.g., time, frequency, and power). Examples of suchmultiple-access systems include fourth generation (4G) systems such asLong Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, orLTE-A Pro systems, and fifth generation (5G) systems which may bereferred to as New Radio (NR) systems. These systems may employtechnologies such as code division multiple access (CDMA), time divisionmultiple access (TDMA), frequency division multiple access (FDMA),orthogonal frequency division multiple access (OFDMA), or discreteFourier transform spread orthogonal frequency division multiplexing(DFT-S-OFDM). A wireless multiple-access communications system mayinclude one or more base stations or one or more network access nodes,each simultaneously supporting communication for multiple communicationdevices, which may be otherwise known as user equipment (UE).

Wireless communications systems may support broadcasting of packets to aplurality of UEs. The transmitter (e.g., a network node, base station,etc.) may broadcast multiple packets to multiple receivers (e.g., UEs).The broadcasting may be repeated blindly without the transmitter havingidentified packets that have been received by the receivers.

SUMMARY

The described techniques relate to improved methods, systems, devices,and apparatuses that support broadcasting packets using network codingvia sidelink with feedback. Generally, the described techniques providefor enabling a transmitter (e.g., a base station) to leverage feedbackfrom receivers (e.g., a user equipment (UE)) for broadcasted packets todetermine which packets of a set to retransmit. The transmitter mayidentify a set of packets for broadcast to a set of UEs and transmit aset of network encoded packets based on the set of packets. The UEs mayeach rebroadcast successfully received network encoded packets viasidelink communications. When each UE has received a first round ofnetwork encoded packets from both the transmitter as wells as from otherUEs, each UE may report to the original transmitter via feedback. Thefeedback may indicate successfully received packets at each UE.

The transmitter may generate an updated set of network encoded packetsbased on the feedback received from one or more of the UEs. Inparticular, the transmitter may determine, based on the feedback, whichof the network encoded packets received at each UE would actually besuccessfully decoded by the UE. The updated set of network encodedpackets may be determined based on the set of network encoded packetsminus the successfully received network encoded packets (afterdetermination by the transmitter) included in each of the subsets (e.g.,an intersection of the subsets). In some examples, the updated set ofnetwork encoded packets may further be determined based on the set ofnetwork encoded packets minus the successfully received packets includedin any of the subsets (e.g., a union of the subsets). The transmittermay continue to update and transmit the updated set of network encodedpackets based on feedback until the transmitter determines that each UEhas recovered the set of packets. In each round, the transmitter maydecode the successfully received packets included in each of the subsetsindicated in the feedback to determine that each UE has recovered theset of packets.

A method of wireless communication at a network node is described. Themethod may include transmitting, to a plurality of UEs, a set of one ormore network encoded packets representing a set of one or more packetsidentified for broadcast to the plurality of UEs, receiving feedbackfrom each of one or more of the plurality of UEs, the feedbackindicating, as respective subsets of the set of one or more networkencoded packets, one or more successfully received network encodedpackets of the set of one or more network encoded packets at each of theone or more UEs, determining, based on the feedback indicative of theone or more successfully received network encoded packets, a subset ofthe set of one or more network encoded packets that was successfullyreceived for each of the one or more of the plurality of UEs providingthe feedback, generating, based on the feedback, an updated set of oneor more network encoded packets based on the set of one or more packets,where the updated set of one or more network encoded packets excludesthe subset of the set of one or more network encoded packets that wassuccessfully received, and transmitting the updated set of one or morenetwork encoded packets to the plurality of UEs.

An apparatus for wireless communication at a network node is described.The apparatus may include a processor, memory coupled with theprocessor, and instructions stored in the memory. The instructions maybe executable by the processor to cause the apparatus to transmit, to aplurality of UEs, a set of one or more network encoded packetsrepresenting a set of one or more packets identified for broadcast tothe plurality of UEs, receive feedback from each of one or more of theplurality of UEs, the feedback indicating, as respective subsets of theset of one or more network encoded packets, one or more successfullyreceived network encoded packets of the set of one or more networkencoded packets at each of the one or more UEs, determine, based on thefeedback indicative of the one or more successfully received networkencoded packets, a subset of the set of one or more network encodedpackets that was successfully received for each of the one or more ofthe plurality of UEs providing the feedback, generate, based on thefeedback, an updated set of one or more network encoded packets based onthe set of one or more packets, where the updated set of one or morenetwork encoded packets excludes the subset of the set of one or morenetwork encoded packets that was successfully received, and transmit theupdated set of one or more network encoded packets to the plurality ofUEs.

Another apparatus for wireless communication at a network node isdescribed. The apparatus may include means for transmitting, to aplurality of UEs, a set of one or more network encoded packetsrepresenting a set of one or more packets identified for broadcast tothe plurality of UEs, receiving feedback from each of one or more of theplurality of UEs, the feedback indicating, as respective subsets of theset of one or more network encoded packets, one or more successfullyreceived network encoded packets of the set of one or more networkencoded packets at each of the one or more UEs, determining, based onthe feedback indicative of the one or more successfully received networkencoded packets, a subset of the set of one or more network encodedpackets that was successfully received for each of the one or more ofthe plurality of UEs providing the feedback, generating, based on thefeedback, an updated set of one or more network encoded packets based onthe set of one or more packets, where the updated set of one or morenetwork encoded packets excludes the subset of the set of one or morenetwork encoded packets that was successfully received, and transmittingthe updated set of one or more network encoded packets to the pluralityof UEs.

A non-transitory computer-readable medium storing code for wirelesscommunication at a network node is described. The code may includeinstructions executable by a processor to transmit, to a plurality ofUEs, a set of one or more network encoded packets representing a set ofone or more packets identified for broadcast to the plurality of UEs,receive feedback from each of one or more of the plurality of UEs, thefeedback indicating, as respective subsets of the set of one or morenetwork encoded packets, one or more successfully received networkencoded packets of the set of one or more network encoded packets ateach of the one or more UEs, determine, based on the feedback indicativeof the one or more successfully received network encoded packets, asubset of the set of one or more network encoded packets that wassuccessfully received for each of the one or more of the plurality ofUEs providing the feedback, generate, based on the feedback, an updatedset of one or more network encoded packets based on the set of one ormore packets, where the updated set of one or more network encodedpackets excludes the subset of the set of one or more network encodedpackets that was successfully received, and transmit the updated set ofone or more network encoded packets to the plurality of UEs.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for continuing to updateand transmit the updated set of one or more network encoded packetsbased on additional feedback received from the one or more of theplurality of UEs until the network node determines that each UE of theplurality of UEs may have recovered the set of one or more packets.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for decoding the one ormore successfully received packets included in each of the subsetsindicated in the feedback and the additional feedback, where the networknode determines that each UE of the plurality of UEs may have recoveredthe set of one or more packets based on the decoding.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, determining the subset of theset of one or more network encoded packets may include operations,features, means, or instructions for determining an intersection of eachof the subsets indicated in the feedback to identify the one or moresuccessfully received packets included in each of the subsets.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining, based onthe feedback indicative of the one or more successfully received networkencoded packets, a second subset of the set of one or more networkencoded packets that was successfully received at any of the one or moreof the plurality of UEs providing the feedback, where the updated set ofone or more network encoded packets further excludes the second subsetof the set of one or more network encoded packets.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, determining the second subsetof the set of one or more network encoded packets may includeoperations, features, means, or instructions for determining a union ofeach of the subsets indicated in the feedback to identify the one ormore successfully received packets included in each of the subsets.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, receiving the feedback mayinclude operations, features, means, or instructions for receiving thefeedback via a packet data convergence protocol (PDCP) status report, aradio link control (RLC) status report, or a hybrid automatic repeatrequest (HARD) message.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, receiving the feedback mayinclude operations, features, means, or instructions for receiving thefeedback in a network coding sub-layer, where the feedback indicates adecoding status of each packet of the set of one or more packets.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving a channelstate information message in conjunction with the feedback, anddetermining one or more encoding metrics for transmission of the updatedset of one or more packets based on the channel state informationmessage.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, determining the one or moreencoding metrics may include operations, features, means, orinstructions for determining a modulation and coding scheme, an encodingrate, or both.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, receiving the channel stateinformation message may include operations, features, means, orinstructions for receiving the channel state information message basedon the feedback indicating a negative acknowledgement for one or more ofthe set of one or more network encoded packets.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting, to one ormore of the plurality of UEs, an indication of one or more networkcoding parameters, where at least the updated set of one or more networkencoded packets may be transmitted to the plurality of UEs in accordancewith the one or more network coding parameters.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, transmitting the indicationof the one or more network coding parameters may include operations,features, means, or instructions for transmitting an indication of anetwork coding algorithm, a network encoding function, a networkencoding matrix, a number of decoding iterations, or any combinationthereof.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, transmitting the indicationof the one or more network coding parameters may include operations,features, means, or instructions for transmitting the one or morenetwork coding parameters using medium access control-control element(MAC-CE) signaling, downlink control information signaling, radioresource control signaling, or any combination thereof.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, transmitting the indicationof the one or more network coding parameters may include operations,features, means, or instructions for transmitting an indication toswitch from one or more prior network coding parameters to the one ormore network coding parameters.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving, from the oneor more of the plurality of UEs, a request for the one or more networkcoding parameters, where the indication of the one or more networkcoding parameters may be transmitted based on receiving the request.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, receiving the request mayinclude operations, features, means, or instructions for receiving, therequest using medium access control-control element (MAC-CE) signalingor uplink control information signaling.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for identifying the set ofone or more packets from a packet pool scheduled for broadcast to theplurality of UEs.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for identifying one or moreadditional packets for broadcast to the plurality of UEs based on theone or more additional packets being added to the packet pool.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for encoding the set of oneor more network encoded packets according to a Luby transform (LT) code,where each network encoded packet of the set of one or more networkencoded packets may be constructed from one or more packets of the setof one or more packets identified for broadcast to the plurality of UEsaccording to a distribution.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the distribution includes anideal soliton distribution, a robust soliton distribution, or anycombination thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 through 3 illustrate examples of wireless communications systemsthat support broadcasting packets using network coding via sidelink withfeedback in accordance with aspects of the present disclosure.

FIGS. 4 and 5 illustrate examples of process flows that supportbroadcasting packets using network coding via sidelink with feedback inaccordance with aspects of the present disclosure.

FIGS. 6 and 7 show block diagrams of devices that support broadcastingpackets using network coding via sidelink with feedback in accordancewith aspects of the present disclosure.

FIG. 8 shows a block diagram of a communications manager that supportsbroadcasting packets using network coding via sidelink with feedback inaccordance with aspects of the present disclosure.

FIG. 9 shows a diagram of a system including a device that supportsbroadcasting packets using network coding via sidelink with feedback inaccordance with aspects of the present disclosure.

FIGS. 10 and 11 show flowcharts illustrating methods that supportbroadcasting packets using network coding via sidelink with feedback inaccordance with aspects of the present disclosure.

DETAILED DESCRIPTION

Wireless communications systems may support broadcasting of networkcoded packets to a plurality of UEs. The transmitter (e.g., a networknode, base station, etc.) may broadcast multiple packets to multiplereceivers (e.g., UEs). Additionally, receivers may broadcast packetsdirectly to one another in sidelink communication channels withouttransmitting through a base station or through a relay point. A sidelinkcommunication may be an example of device-to-device (D2D) communication,vehicle-to-everything (V2X) communication, or another example ofsidelink communication in a wireless communications system. Thebroadcasting may be repeated blindly without the transmitter havingidentified network coded packets that have been decoded by thereceivers. That is, if the broadcasting system does not utilize feedbackassociated with packets, the transmitter may continue to transmitpackets blindly without any indication of packets that have actuallybeen decoded by the UEs. Thus, the transmitter may rebroadcast packetsin a wasteful manner, since some packets may have been decoded by allUEs. Thus, the lack of feedback may result in waste, unnecessaryduplication of packets, and low efficiency.

Techniques described herein may leverage feedback for broadcastedpackets to determine which packets of a set to retransmit. Thetransmitter may identify a set of packets for broadcast to a set of UEsand transmit a set of network encoded packets based on the set ofpackets. In some examples, the transmitter may encode the set of networkencoded packets according to a Luby transform (LT) code, where eachnetwork encoded packet of the set of network encoded packets may beconstructed from one or more packets according to a distribution (e.g.,an ideal soliton distribution, a robust soliton distribution, amongother examples).

The UEs may each rebroadcast successfully received network encodedpackets via sidelink communications. When each UE has received a firstround of network encoded packets from both the transmitter as wells asfrom other UEs, each UE may report to the original transmitter viafeedback. The feedback may indicate successfully received packets ateach UE. In some examples, the UEs may decode the packets concurrentwith transmitting the feedback.

The feedback may be received via one or more hybrid automatic repeatrequest (HARD) messages, using a packet data convergence protocol (PDCP)status report, or a radio link control (RLC) status report. Further, thetransmitter may configure the UEs with network encoding parameters, suchas a network coding algorithm, a network coding function, a networkencoding matrix, a number of decoding iterations, or a combinationthereof. Thus, the transmitter and the UEs may be synchronized such thatthe transmitter may encode the packets and the UEs may decode thepackets. In some examples, the transmitter may adjust encoding metrics,such as a modulation and coding scheme (MCS) or encoding rate, based onthe feedback such that the UEs may have a higher probability ofsuccessfully decoding packets. These and other implementations arefurther described with respect to the figures.

The transmitter may generate an updated set of network encoded packetsbased on the feedback received from one or more of the UEs. The updatedset of network encoded packets may be determined based on the set ofnetwork encoded packets minus the successfully received network encodedpackets included in each of the subsets (e.g., an intersection of thesubsets). In some examples, the updated set of network encoded packetsmay further be determined based on the set of network encoded packetsminus the successfully received packets included in any of the subsets(e.g., a union of the subsets). The transmitter may continue to updateand transmit the updated set of network encoded packets based onfeedback until the transmitter determines that each UE has recovered theset of packets. In some examples, the transmitter may decode thesuccessfully received packets included in each of the subsets indicatedin the feedback to determine that each UE has recovered the set ofpackets.

Particular aspects of the subject matter described herein may beimplemented to realize one or more advantages. The described techniquesmay support improvements in the packet broadcasting framework,decreasing signaling overhead, and improving reliability, among otheradvantages. As such, supported techniques may include improved networkoperations and, in some examples, may promote network efficiencies,among other benefits. Aspects of the disclosure are initially describedin the context of wireless communications systems. Aspects of thedisclosure are further illustrated by and described with reference toprocess flows, apparatus diagrams, system diagrams, and flowcharts thatrelate to broadcasting packets using network coding via sidelink withfeedback.

FIG. 1 illustrates an example of a wireless communications system 100that supports broadcasting packets using network coding via sidelinkwith feedback in accordance with aspects of the present disclosure. Thewireless communications system 100 may include one or more base stations105, one or more UEs 115, and a core network 130. In some examples, thewireless communications system 100 may be a Long Term Evolution (LTE)network, an LTE-Advanced (LTE-A) network, an LTE-A Pro network, or a NewRadio (NR) network. In some examples, the wireless communications system100 may support enhanced broadband communications, ultra-reliable (e.g.,mission critical) communications, low latency communications,communications with low-cost and low-complexity devices, or anycombination thereof.

The base stations 105 may be dispersed throughout a geographic area toform the wireless communications system 100 and may be devices indifferent forms or having different capabilities. The base stations 105and the UEs 115 may wirelessly communicate via one or more communicationlinks 125. Each base station 105 may provide a coverage area 110 overwhich the UEs 115 and the base station 105 may establish one or morecommunication links 125. The coverage area 110 may be an example of ageographic area over which a base station 105 and a UE 115 may supportthe communication of signals according to one or more radio accesstechnologies.

The UEs 115 may be dispersed throughout a coverage area 110 of thewireless communications system 100, and each UE 115 may be stationary,or mobile, or both at different times. The UEs 115 may be devices indifferent forms or having different capabilities. Some example UEs 115are illustrated in FIG. 1. The UEs 115 described herein may be able tocommunicate with various types of devices, such as other UEs 115, thebase stations 105, or network equipment (e.g., core network nodes, relaydevices, integrated access and backhaul (IAB) nodes, or other networkequipment), as shown in FIG. 1.

The base stations 105 may communicate with the core network 130, or withone another, or both. For example, the base stations 105 may interfacewith the core network 130 through one or more backhaul links 120 (e.g.,via an S1, N2, N3, or other interface). The base stations 105 maycommunicate with one another over the backhaul links 120 (e.g., via anX2, Xn, or other interface) either directly (e.g., directly between basestations 105), or indirectly (e.g., via core network 130), or both. Insome examples, the backhaul links 120 may be or include one or morewireless links.

One or more of the base stations 105 described herein may include or maybe referred to by a person having ordinary skill in the art as a basetransceiver station, a radio base station, an access point, a radiotransceiver, a NodeB, an eNodeB (eNB), a next-generation NodeB or agiga-NodeB (either of which may be referred to as a gNB), a Home NodeB,a Home eNodeB, or other suitable terminology.

A UE 115 may include or may be referred to as a mobile device, awireless device, a remote device, a handheld device, or a subscriberdevice, or some other suitable terminology, where the “device” may alsobe referred to as a unit, a station, a terminal, or a client, amongother examples. A UE 115 may also include or may be referred to as apersonal electronic device such as a cellular phone, a personal digitalassistant (PDA), a tablet computer, a laptop computer, or a personalcomputer. In some examples, a UE 115 may include or be referred to as awireless local loop (WLL) station, an Internet of Things (IoT) device,an Internet of Everything (IoE) device, or a machine type communications(MTC) device, among other examples, which may be implemented in variousobjects such as appliances, or vehicles, meters, among other examples.

The UEs 115 described herein may be able to communicate with varioustypes of devices, such as other UEs 115 that may sometimes act as relaysas well as the base stations 105 and the network equipment includingmacro eNBs or gNBs, small cell eNBs or gNBs, or relay base stations,among other examples, as shown in FIG. 1.

The UEs 115 and the base stations 105 may wirelessly communicate withone another via one or more communication links 125 over one or morecarriers. The term “carrier” may refer to a set of radio frequencyspectrum resources having a defined physical layer structure forsupporting the communication links 125. For example, a carrier used fora communication link 125 may include a portion of a radio frequencyspectrum band (e.g., a bandwidth part (BWP)) that is operated accordingto one or more physical layer channels for a given radio accesstechnology (e.g., LTE, LTE-A, LTE-A Pro, NR). Each physical layerchannel may carry acquisition signaling (e.g., synchronization signals,system information), control signaling that coordinates operation forthe carrier, user data, or other signaling. The wireless communicationssystem 100 may support communication with a UE 115 using carrieraggregation or multi-carrier operation. A UE 115 may be configured withmultiple downlink component carriers and one or more uplink componentcarriers according to a carrier aggregation configuration. Carrieraggregation may be used with both frequency division duplexing (FDD) andtime division duplexing (TDD) component carriers.

Signal waveforms transmitted over a carrier may be made up of multiplesubcarriers (e.g., using multi-carrier modulation (MCM) techniques suchas orthogonal frequency division multiplexing (OFDM) or discrete Fouriertransform spread OFDM (DFT-S-OFDM)). In a system employing MCMtechniques, a resource element may consist of one symbol period (e.g., aduration of one modulation symbol) and one subcarrier, where the symbolperiod and subcarrier spacing are inversely related. The number of bitscarried by each resource element may depend on the modulation scheme(e.g., the order of the modulation scheme, the coding rate of themodulation scheme, or both). Thus, the more resource elements that a UE115 receives and the higher the order of the modulation scheme, thehigher the data rate may be for the UE 115. A wireless communicationsresource may refer to a combination of a radio frequency spectrumresource, a time resource, and a spatial resource (e.g., spatial layersor beams), and the use of multiple spatial layers may further increasethe data rate or data integrity for communications with a UE 115.

The time intervals for the base stations 105 or the UEs 115 may beexpressed in multiples of a basic time unit which may, for example,refer to a sampling period of T_(s)=1/(Δf_(max)·N_(f)) seconds, whereΔf_(max) may represent the maximum supported subcarrier spacing, andN_(f) may represent the maximum supported discrete Fourier transform(DFT) size. Time intervals of a communications resource may be organizedaccording to radio frames each having a specified duration (e.g., 10milliseconds (ms)). Each radio frame may be identified by a system framenumber (SFN) (e.g., ranging from 0 to 1023).

Each frame may include multiple consecutively numbered subframes orslots, and each subframe or slot may have the same duration. In someexamples, a frame may be divided (e.g., in the time domain) intosubframes, and each subframe may be further divided into a number ofslots. Alternatively, each frame may include a variable number of slots,and the number of slots may depend on subcarrier spacing. Each slot mayinclude a number of symbol periods (e.g., depending on the length of thecyclic prefix prepended to each symbol period). In some wirelesscommunications systems 100, a slot may further be divided into multiplemini-slots containing one or more symbols. Excluding the cyclic prefix,each symbol period may contain one or more (e.g., N_(f)) samplingperiods. The duration of a symbol period may depend on the subcarrierspacing or frequency band of operation.

A subframe, a slot, a mini-slot, or a symbol may be the smallestscheduling unit (e.g., in the time domain) of the wirelesscommunications system 100 and may be referred to as a transmission timeinterval (TTI). In some examples, the TTI duration (e.g., the number ofsymbol periods in a TTI) may be variable. Additionally or alternatively,the smallest scheduling unit of the wireless communications system 100may be dynamically selected (e.g., in bursts of shortened TTIs (sTTIs)).

Physical channels may be multiplexed on a carrier according to varioustechniques. A physical control channel and a physical data channel maybe multiplexed on a downlink carrier, for example, using one or more oftime division multiplexing (TDM) techniques, frequency divisionmultiplexing (FDM) techniques, or hybrid TDM-FDM techniques. A controlregion (e.g., a control resource set (CORESET)) for a physical controlchannel may be defined by a number of symbol periods and may extendacross the system bandwidth or a subset of the system bandwidth of thecarrier. One or more control regions (e.g., CORESETs) may be configuredfor a set of the UEs 115. For example, one or more of the UEs 115 maymonitor or search control regions for control information according toone or more search space sets, and each search space set may include oneor multiple control channel candidates in one or more aggregation levelsarranged in a cascaded manner. An aggregation level for a controlchannel candidate may refer to a number of control channel resources(e.g., control channel elements (CCEs)) associated with encodedinformation for a control information format having a given payloadsize. Search space sets may include common search space sets configuredfor sending control information to multiple UEs 115 and UE-specificsearch space sets for sending control information to a specific UE 115.

In some examples, a base station 105 may be movable and thereforeprovide communication coverage for a moving geographic coverage area110. In some examples, different geographic coverage areas 110associated with different technologies may overlap, but the differentgeographic coverage areas 110 may be supported by the same base station105. In other examples, the overlapping geographic coverage areas 110associated with different technologies may be supported by differentbase stations 105. The wireless communications system 100 may include,for example, a heterogeneous network in which different types of thebase stations 105 provide coverage for various geographic coverage areas110 using the same or different radio access technologies.

The wireless communications system 100 may support synchronous orasynchronous operation. For synchronous operation, the base stations 105may have similar frame timings, and transmissions from different basestations 105 may be approximately aligned in time. For asynchronousoperation, the base stations 105 may have different frame timings, andtransmissions from different base stations 105 may, in some examples,not be aligned in time. The techniques described herein may be used foreither synchronous or asynchronous operations.

Some UEs 115, such as MTC or IoT devices, may be low cost or lowcomplexity devices and may provide for automated communication betweenmachines (e.g., via Machine-to-Machine (M2M) communication). M2Mcommunication or MTC may refer to data communication technologies thatallow devices to communicate with one another or a base station 105without human intervention. In some examples, M2M communication or MTCmay include communications from devices that integrate sensors or metersto measure or capture information and relay such information to acentral server or application program that makes use of the informationor presents the information to humans interacting with the applicationprogram. Some UEs 115 may be designed to collect information or enableautomated behavior of machines or other devices. Examples ofapplications for MTC devices include smart metering, inventorymonitoring, water level monitoring, equipment monitoring, healthcaremonitoring, wildlife monitoring, weather and geological eventmonitoring, fleet management and tracking, remote security sensing,physical access control, and transaction-based business charging.

Some UEs 115 may be configured to employ operating modes that reducepower consumption, such as half-duplex communications (e.g., a mode thatsupports one-way communication via transmission or reception, but nottransmission and reception simultaneously). In some examples,half-duplex communications may be performed at a reduced peak rate.Other power conservation techniques for the UEs 115 include entering apower saving deep sleep mode when not engaging in active communications,operating over a limited bandwidth (e.g., according to narrowbandcommunications), or a combination of these techniques. For example, someUEs 115 may be configured for operation using a narrowband protocol typethat is associated with a defined portion or range (e.g., set ofsubcarriers or resource blocks (RBs)) within a carrier, within aguard-band of a carrier, or outside of a carrier.

The wireless communications system 100 may be configured to supportultra-reliable communications or low-latency communications, or variouscombinations thereof. For example, the wireless communications system100 may be configured to support ultra-reliable low-latencycommunications (URLLC) or mission critical communications. The UEs 115may be designed to support ultra-reliable, low-latency, or criticalfunctions (e.g., mission critical functions). Ultra-reliablecommunications may include private communication or group communicationand may be supported by one or more mission critical services such asmission critical push-to-talk (MCPTT), mission critical video (MCVideo),or mission critical data (MCData). Support for mission criticalfunctions may include prioritization of services, and mission criticalservices may be used for public safety or general commercialapplications. The terms ultra-reliable, low-latency, mission critical,and ultra-reliable low-latency may be used interchangeably herein.

In some examples, a UE 115 may also be able to communicate directly withother UEs 115 over a device-to-device (D2D) communication link 135(e.g., using a peer-to-peer (P2P) or D2D protocol). One or more UEs 115utilizing D2D communications may be within the geographic coverage area110 of a base station 105. Other UEs 115 in such a group may be outsidethe geographic coverage area 110 of a base station 105 or be otherwiseunable to receive transmissions from a base station 105. In someexamples, groups of the UEs 115 communicating via D2D communications mayutilize a one-to-many (1:M) system in which each UE 115 transmits toevery other UE 115 in the group. In some examples, a base station 105facilitates the scheduling of resources for D2D communications. In othercases, D2D communications are carried out between the UEs 115 withoutthe involvement of a base station 105.

In some systems, the D2D communication link 135 may be an example of acommunication channel, such as a sidelink communication channel, betweenvehicles (e.g., UEs 115). In some examples, vehicles may communicateusing vehicle-to-everything (V2X) communications, vehicle-to-vehicle(V2V) communications, or some combination of these. A vehicle may signalinformation related to traffic conditions, signal scheduling, weather,safety, emergencies, or any other information relevant to a V2X system.In some examples, vehicles in a V2X system may communicate with roadsideinfrastructure, such as roadside units, or with the network via one ormore network nodes (e.g., base stations 105) using vehicle-to-network(V2N) communications, or with both.

The core network 130 may provide user authentication, accessauthorization, tracking, Internet Protocol (IP) connectivity, and otheraccess, routing, or mobility functions. The core network 130 may be anevolved packet core (EPC) or 5G core (5GC), which may include at leastone control plane entity that manages access and mobility (e.g., amobility management entity (MME), an access and mobility managementfunction (AMF)) and at least one user plane entity that routes packetsor interconnects to external networks (e.g., a serving gateway (S-GW), aPacket Data Network (PDN) gateway (P-GW), or a user plane function(UPF)). The control plane entity may manage non-access stratum (NAS)functions such as mobility, authentication, and bearer management forthe UEs 115 served by the base stations 105 associated with the corenetwork 130. User IP packets may be transferred through the user planeentity, which may provide IP address allocation as well as otherfunctions. The user plane entity may be connected to the networkoperators IP services 150. The operators IP services 150 may includeaccess to the Internet, Intranet(s), an IP Multimedia Subsystem (IMS),or a Packet-Switched Streaming Service.

Some of the network devices, such as a base station 105, may includesubcomponents such as an access network entity 140, which may be anexample of an access node controller (ANC). Each access network entity140 may communicate with the UEs 115 through one or more other accessnetwork transmission entities 145, which may be referred to as radioheads, smart radio heads, or transmission/reception points (TRPs). Eachaccess network transmission entity 145 may include one or more antennapanels. In some configurations, various functions of each access networkentity 140 or base station 105 may be distributed across various networkdevices (e.g., radio heads and ANCs) or consolidated into a singlenetwork device (e.g., a base station 105).

The wireless communications system 100 may operate using one or morefrequency bands, typically in the range of 300 megahertz (MHz) to 300gigahertz (GHz). Generally, the region from 300 MHz to 3 GHz is known asthe ultra-high frequency (UHF) region or decimeter band because thewavelengths range from approximately one decimeter to one meter inlength. The UHF waves may be blocked or redirected by buildings andenvironmental features, but the waves may penetrate structuressufficiently for a macro cell to provide service to the UEs 115 locatedindoors. The transmission of UHF waves may be associated with smallerantennas and shorter ranges (e.g., less than 100 kilometers) compared totransmission using the smaller frequencies and longer waves of the highfrequency (HF) or very high frequency (VHF) portion of the spectrumbelow 300 MHz.

The wireless communications system 100 may utilize both licensed andunlicensed radio frequency spectrum bands. For example, the wirelesscommunications system 100 may employ License Assisted Access (LAA),LTE-Unlicensed (LTE-U) radio access technology, or NR technology in anunlicensed band such as the 5 GHz industrial, scientific, and medical(ISM) band. When operating in unlicensed radio frequency spectrum bands,devices such as the base stations 105 and the UEs 115 may employ carriersensing for collision detection and avoidance. In some examples,operations in unlicensed bands may be based on a carrier aggregationconfiguration in conjunction with component carriers operating in alicensed band (e.g., LAA). Operations in unlicensed spectrum may includedownlink transmissions, uplink transmissions, P2P transmissions, or D2Dtransmissions, among other examples.

A base station 105 or a UE 115 may be equipped with multiple antennas,which may be used to employ techniques such as transmit diversity,receive diversity, multiple-input multiple-output (MIMO) communications,or beamforming. The antennas of a base station 105 or a UE 115 may belocated within one or more antenna arrays or antenna panels, which maysupport MIMO operations or transmit or receive beamforming. For example,one or more base station antennas or antenna arrays may be co-located atan antenna assembly, such as an antenna tower. In some examples,antennas or antenna arrays associated with a base station 105 may belocated in diverse geographic locations. A base station 105 may have anantenna array with a number of rows and columns of antenna ports thatthe base station 105 may use to support beamforming of communicationswith a UE 115. Likewise, a UE 115 may have one or more antenna arraysthat may support various MIMO or beamforming operations. Additionally oralternatively, an antenna panel may support radio frequency beamformingfor a signal transmitted via an antenna port.

Beamforming, which may also be referred to as spatial filtering,directional transmission, or directional reception, is a signalprocessing technique that may be used at a transmitting device or areceiving device (e.g., a base station 105, a UE 115) to shape or steeran antenna beam (e.g., a transmit beam, a receive beam) along a spatialpath between the transmitting device and the receiving device.Beamforming may be achieved by combining the signals communicated viaantenna elements of an antenna array such that some signals propagatingat particular orientations with respect to an antenna array experienceconstructive interference while others experience destructiveinterference. The adjustment of signals communicated via the antennaelements may include a transmitting device or a receiving deviceapplying amplitude offsets, phase offsets, or both to signals carriedvia the antenna elements associated with the device. The adjustmentsassociated with each of the antenna elements may be defined by abeamforming weight set associated with a particular orientation (e.g.,with respect to the antenna array of the transmitting device orreceiving device, or with respect to some other orientation).

The wireless communications system 100 may be a packet-based networkthat operates according to a layered protocol stack. In the user plane,communications at the bearer or Packet Data Convergence Protocol (PDCP)layer may be IP-based. An RLC layer may perform packet segmentation andreassembly to communicate over logical channels. A Medium Access Control(MAC) layer may perform priority handling and multiplexing of logicalchannels into transport channels. The MAC layer may also use errordetection techniques, error correction techniques, or both to supportretransmissions at the MAC layer to improve link efficiency. In thecontrol plane, the Radio Resource Control (RRC) protocol layer mayprovide establishment, configuration, and maintenance of an RRCconnection between a UE 115 and a base station 105 or a core network 130supporting radio bearers for user plane data. At the physical layer,transport channels may be mapped to physical channels.

The UEs 115 and the base stations 105 may support retransmissions ofdata to increase the likelihood that data is received successfully. HARQfeedback is one technique for increasing the likelihood that data isreceived correctly over a communication link 125. HARQ may include acombination of error detection (e.g., using a cyclic redundancy check(CRC)), forward error correction (FEC), and retransmission (e.g.,automatic repeat request (ARQ)). HARQ may improve throughput at the MAClayer in poor radio conditions (e.g., low signal-to-noise conditions).In some examples, a device may support same-slot HARQ feedback, wherethe device may provide HARQ feedback in a specific slot for datareceived in a previous symbol in the slot. In other cases, the devicemay provide HARQ feedback in a subsequent slot, or according to someother time interval.

Some wireless communications systems 100 may support broadcastingpackets to a plurality of UEs 115. The packets may be broadcast by anetwork node, which may be an example of a base station 105, UE 115, orthe like. The transmitter may broadcast multiple packets to multiplereceivers (e.g., UEs 115). The broadcasting may be repeated blindlywithout the transmitter knowing whether packets have been received ordecoded by the receivers. That is, if the wireless communications system100 does not utilize feedback associated with the packets, thetransmitter may continue to transmit packets blindly without anyindication of packets that have actually been decoded by the UEs 115.Thus, the transmitter may rebroadcast packets in a wasteful manner,since some packets may have been decoded by all UEs 115. Thus, the lackof feedback may result in waste, unnecessary duplication of packets, andlow efficiency.

Techniques described herein support a packet broadcasting design thatuses feedback received from the UEs 115. The transmitter (e.g., basestation 105) may identify a set of packets for broadcasting to aplurality of UEs 115 and transmit a set of network encoded packets basedon the set of packets. The UEs 115 may each rebroadcast successfullyreceived network encoded packets via sidelink communications. When eachUE 115 has received a first round of network encoded packets from boththe transmitter as well as from other UEs 115, each UE 115 may report tothe original transmitter via feedback. The feedback may indicatesuccessfully received network encoded packets at each UE 115. In someexamples, the UEs 115 may decode the packets concurrent withtransmitting the feedback.

Each of the receiving UEs 115 may provide feedback associated withreceiving the broadcasted network encoded packets. For example, feedbackreceived from a particular UE 115 may indicate a subset of successfullyreceived packets of the set of network encoded packets. The transmittermay generate an updated set of network encoded packets based on thefeedback received from one or more of the UEs 115. The updated set ofnetwork encoded packets may be determined based on the set of networkencoded packets minus the successfully received packets included in eachof the subsets (e.g., an intersection of the subsets). In some examples,the updated set of network encoded packets may further be determinedbased on the set of network encoded packets minus the successfullyreceived packets included in any of the subsets (e.g., a union of thesubsets). The transmitter may continue to update and transmit theupdated set of network encoded packets based on feedback until thetransmitter determines that each UE 115 of the UEs 115 has recovered theset of packets. In some examples, the transmitter may decode thesuccessfully received packets included in each of the subsets indicatedin the feedback to determine that each UE 115 of the UEs 115 hasrecovered the set of packets.

Using this technique, the transmitter may reduce waste and duplicationof packets by retransmitting packets that have not been decoded by theUEs 115. This may result in increased efficiencies in the wirelesscommunications system 100, and more particularly, a broadcasting system.

Different types of feedback may support these techniques. For example,the transmitter (e.g., base station 105) may use HARQ messages receivedfrom the UEs 115 to update the sets of packets. The HARQ message mayindicate an acknowledgement (ACK) or negative-acknowledgement (NACK) forone or more packets. Thus, based on the ACKs and NAKs, the transmittermay determine which packets were successfully received by which UEs 115.In some examples, the feedback is received via one or more PDCP statusreports, one or more RLC status reports, or the like. Further to supportthese techniques, the transmitter may configure the UEs 115 with networkcoding parameters, which the UEs 115 may use to decode the packets. Thetransmitter may update the various encoding metrics during thebroadcasting to increase the likelihood that the UEs 115 are able todecode the packets. For example, the transmitter may receive a channelstate information (CSI) report based on receiving a NACK for one or morepackets and update the modulation and coding scheme or encoding ratebased on the CSI report.

FIG. 2 illustrates an example of a wireless communications system 200that supports broadcasting packets using network coding via sidelinkwith feedback in accordance with aspects of the present disclosure. Insome examples, the wireless communications system 200 may implementaspects of the wireless communications system 100. For example, thewireless communications system 200 may include a network entity 205 andUEs 215, which may be examples of the corresponding devices describedwith reference to FIG. 1. The wireless communications system 200 mayillustrate an example of a packet broadcasting system. The networkentity 205 may be an example of a base station 105 described withreference to FIG. 1, a network node, a transmitter, or the like. Thewireless communications system 200 may include features for improvedpacket transmission operations, among other benefits.

The UEs 215 may transmit and receive communications as scheduled by thenetwork entity 205. For example, the UEs 215 may communicate with thenetwork entity via direct links 220 (e.g., communication links 125described with reference to FIG. 1). Additionally or alternatively, theUEs 215 may communicate directly with one another via sidelinkconnections 225 without transmitting through the network entity 205. Thesidelink connections 225 may illustrate examples of D2D communication,V2X communication, or another example of sidelink communication in thewireless communications system 200.

In some cases, the wireless communications system 200 may supportbroadcasting packets by the network entity 205 to the UEs 215 via thedirect links 220. The network entity 205 may repeat the broadcastingblindly without knowing whether the packets were received or decoded bythe UEs 215. That is, if the wireless communications system 200 does notutilize feedback associated with the packets, the network entity 205 maycontinue to transmit packets blindly without any indication of packetsthat have actually been received or decoded by the UEs 215. Thus, thenetwork entity 205 may rebroadcast packets in a wasteful manner, sincesome packets may have been received or decoded by all UEs 215. Thus, thelack of feedback may result in waste, unnecessary duplication ofpackets, and low efficiency.

Techniques described herein support a packet broadcasting design thatuses feedback received from the UEs 215. The network entity 205 mayidentify a set of packets for broadcasting to the UEs 215 and transmit aset of network encoded packets based on the set of packets via thedirect links 220. The UEs 215 may each rebroadcast successfully receivednetwork encoded packets via the sidelink connections 225. When each UE215 has received a first round of network encoded packets from both thenetwork entity 205 as well as from other UEs 215, each UE 215 may reportto the network entity 205 via feedback on a direct link 220. Thefeedback may indicate successfully received network encoded packets ateach UE 215. In some examples, the UEs 215 may decode the packetsconcurrent with transmitting the feedback.

Each of the receiving UEs 215 may provide feedback associated withreceiving the broadcasted network encoded packets. For example, feedbackreceived from a particular UE 215 may indicate a subset of successfullyreceived network encoded packets of the set of network encoded packets.The network entity 205 may generate an updated set of network encodedpackets based on the feedback received from one or more of the UEs 215.The updated set of network encoded packets may be determined based onthe set of network encoded packets minus the successfully receivednetwork encoded packets included in each of the subsets (e.g., anintersection of the subsets). In some examples, the updated set ofnetwork encoded packets may further be determined based on the set ofnetwork encoded packets minus the successfully received packets includedin any of the subsets (e.g., a union of the subsets). The network entity205 may continue to update and transmit the updated set of networkencoded packets based on feedback until the network entity 205determines that each UE 215 of the UEs 215 has recovered the set ofpackets. In some examples, the transmitter may decode the successfullyreceived packets included in each of the subsets indicated in thefeedback to determine that each UE 215 of the UEs 215 has recovered theset of packets.

Using the techniques described herein, the network entity 205 may reducewaste and duplication of packets by retransmitting packets that have notbeen received by the UEs 215. This may result in increased efficienciesin the wireless communications system 200.

FIG. 3 illustrates an example of a wireless communications system 300that supports broadcasting packets using network coding via sidelinkwith feedback in accordance with aspects of the present disclosure. Insome examples, the wireless communications system 300 may implementaspects of wireless communication systems 100 and 200. For example, thewireless communications system 300 may include a network entity 305 andUEs 315, which may be examples of the corresponding devices describedwith reference to FIGS. 1 and 2. The wireless communications system 300may illustrate an example of a packet broadcasting system. The wirelesscommunications system 300 may include features for improved packettransmission operations, among other benefits.

The network entity 305 may configure the UEs 315 with network codingparameters, such as an encoding matrix, encoding/decoding function, etc.These parameters may be used by the UEs 315 to decode the packets. Forexample, a row of the encoding matrix may indicate an ordering orgrouping of network encoded packets that are transmitted to the UEs 315.The network coding parameters may be signaling using medium accesscontrol-control element (MAC-CE) signaling, downlink control information(DCI), or RRC signaling. In some cases, multiple sets of network codingparameters may be signaled.

The network entity 305 may identify a set of packets for transmission tothe UEs 315. In one example, the network entity 305 identifies the setof packets from a packet pool, which may be a set of packets scheduledfor broadcasting. In some examples, the broadcasting may support acontent streaming service and the packets may correspond to the streamedcontent. From the set of packets, the network entity 305 may encode(e.g., using LT coding) and transmit a set of network encoded packets320-a to the UEs 315 in a broadcast manner. Each of the UEs 315 mayreceive one or more network encoded packets of the set of networkencoded packets 320-a. The UEs 315 may each rebroadcast successfullyreceived network encoded packets 320-a via sidelink connections 330.

When each UE 315 has received a first round of network encoded packets320-a from both the network entity 305 as well as from other UEs 115,each UE 115 may report to the network entity 305 via feedback 325. Thefeedback 325 may indicate a subset of the set of network encoded packets320-a that each UE 315 was able to successfully receive, either directlyfrom the network entity 305 or via the sidelink connections 330. Forexample, the UE 315-a may transmit feedback 325-a that indicates a firstsubset of the set of packets 320-a that the UE 315-a was able tosuccessfully receive, while the UE 315-b transmits feedback 325-b thatindicates a second subset of the set of packets that the UE 315-b wasable to successfully receive, and the UE 315-c transmits feedback 325-cthat indicates a second subset of the set of packets that the UE 315-cwas able to successfully receive.

Based on the received feedback 325, the network entity 305 may generatean updated set of network encoded packets 320-b. The updated set ofnetwork encoded packets 320-b may be determined based on the set ofnetwork encoded packets 320-a minus the successfully received packetsincluded in each of the subsets (e.g., an intersection of the subsets).In some examples, the updated set of network encoded packets 320-b mayfurther be determined based on the set of network encoded packets 320-aminus the successfully received packets included in any of the subsets(e.g., a union of the subsets). The updated set of network encodedpackets 320-b is transmitted to the UEs 315 and the network entity 305may continue to update and transmit updated sets of network encodedpackets 320 based on feedback 325 until the network entity 305determines that each UE 315 of the UEs 315 has recovered the set ofpackets. In some examples, the network entity 305 may decode thesuccessfully received packets included in each of the subsets indicatedin the feedback 325 to determine that each UE 115 of the UEs 115 hasrecovered the set of packets.

As noted herein, the feedback 325 may be an example of one or more HARQmessages. In other cases, the feedback 325 may be an example of a PDCPstatus report or RLC status report. Based on the reports or HARQmessages, the network entity 305 may infer the packet receiving/recoveryresults. In some examples, the UEs 315 may transmit the feedback 325 inthe network coding sub-layer, and such feedback 325 may directlyindicate the receiving success/failure corresponding to each packet. Insome cases, one or more of the UEs 315 may transmit a CSI report tofacilitate MCS selection or rate control. Thus, based on receivedfeedback 325 and a CSI report, the network entity 305 may adjust the MCSor encoding rate to increase likelihood of successful decoding by theUEs 315. In some examples, the CSI report is transmitted when a NACK istransmitted in order to request the updated MCS or data encoding ratefor better data reception.

As noted herein, one or more sets of network coding parameters may beconfigured at the UEs 315. If one set of parameters is configured at oneor more of the UEs 315 and the network entity 305 determines that thetransmission is underperforming (e.g., that the feedback 325 indicatesthat a relatively high number of packets are going undecoded), then thenetwork entity 305 may transmit a new set of network coding parametersto the UEs 315 (e.g., via MAC-CE or DCI). In other cases, the UEs 315may request an updated set of network coding parameters (e.g., viaMAC-CE or uplink control information (UCI)). In either case, after theupdated set of parameters is transmitted, subsequent sets of packets maybe encoded and transmitted according to the updated set of parameters.If multiple sets of network coding parameters are synchronized betweenthe network entity 305 and the UEs 315, then the network entity 305 maytransmit an instruction to switch between sets of parameters (e.g.,based on underperformance or based on a request from a UE 315 receivedvia MAC-CE or UCI) via MAC-CE or DCI.

In some examples, the network entity 305 may encode the network encodedpackets 320 using an LT coding process. In the LT coding process, thenetwork entity 305 may map source symbols of the set of packets to a setof encoding symbols. The LT coding process may employ a degreedistribution Ω, where the degree distribution Ω represents a probabilitymass function of a set of degrees d_(i) (e.g., d₁, d₂, d₃, etc.). Theprobability of randomly selecting a degree d_(i) (i.e., a degree withindex i) from the degree distribution may be represented by ρ(i). In theLT coding process, the degree d_(i) of an ith encoding symbol mayrepresent the quantity of source symbols which the network entity 305may combine into the ith encoding symbol. For example, if the selecteddegree for a first encoding symbol is d₁=2, two source symbols may berandomly selected and combined into the first encoding symbol.Similarly, if the selected degree for a second encoding symbol is d₂=1,a single source symbol may be combined into the second encoding symbol.In some examples, the source symbols may be combined into encodingsymbols using a logic operation such as a logic exclusive OR (XOR)operation. In some examples, each encoding symbol may includeinformation identifying the source symbols used to construct theencoding symbol. For example, the encoding symbol may include indices(e.g., s₁, s₂, s₃, s_(K), etc.) associated with the source symbols usedto construct the encoding symbol. The encoding symbols may betransmitted as the set of network encoded packets 320-a from the networkentity 305 to the UEs 315. In some examples, the LT coding process maybe represented by a generator matrix.

In some examples, one or more encoded packets may be lost based on thetransmission environment. A UE 315 may receive a subset of the set ofnetwork encoded packets 320-a (e.g., a quantity N of encoded packets).The UE 315 may decode the received encoding symbols to obtain the sourcesymbols. The UE 315 may begin a decoding process by identifying anencoding symbol with an index t_(j) that is connected to a single sourcesymbol with an index s_(i). The UE 315 may determine the encoding symbolwith index t_(j) is equivalent to the source symbol with index s_(i).The UE 315 may then apply an XOR operation to each other encoding symbolconnected to the source symbol with index s_(i), and remove all edgesconnected to the source symbol with index s_(i). The UE 315 may repeatthis process until each source symbol is determined from the receivedencoding symbols.

In some examples, the decoding process may fail if there is no encodingsymbol connected to a single source symbol. Accordingly, the degreedistribution Ω of the encoding symbols received at the UE 315 may have adirect impact on the probability of successfully decoding source symbolstransmitted in encoding symbols. For example, in a first degreedistribution (which may in some examples be referred to as an idealsoliton distribution), the probability ρ(i) of selecting a degree d_(i)(where d_(i) is an integer from 1 to K) may be defined by:

$\begin{matrix}{{\rho(i)} = \left\{ \begin{matrix}{\frac{1}{K},{i = 1}} \\{\frac{1}{i\left( {i - 1} \right)},{i = 1},2,\ldots\mspace{14mu},K}\end{matrix} \right.} & (1)\end{matrix}$

The first degree distribution may have a mode (e.g., a high probability)at d_(i)=2.

Alternatively, in a second degree distribution (which in some examplesmay be referred to as a robust soliton distribution), the probability ofselecting the degree d_(i) may be represented by μ(i) rather than ρ(i)of the ideal soliton distribution. The probability μ(i) may be definedby:

$\begin{matrix}{{{\mu(i)} = \frac{{\rho(i)} + {\tau(i)}}{{\sum_{j = 1}^{K}{\rho(j)}} + {\tau(j)}}},} & (2)\end{matrix}$

where τ(i) is a parameter defined in terms of constants c and

${R = {c\sqrt{K}{\ln\left( \frac{K}{\delta} \right)}}},$

as well as a decoding error probability δ. The parameter τ(i) may bedefined for various values of i as:

$\begin{matrix}{{\tau(i)} = \left\{ {\begin{matrix}{\frac{R}{iK},{i = 1},2,\ldots\mspace{14mu},{\frac{K}{R} - 1}} \\{{\frac{R}{K}{\ln\left( \frac{R}{\delta} \right)}},{i = \frac{K}{R}}} \\{0,{otherwise}}\end{matrix}.} \right.} & (3)\end{matrix}$

The robust soliton distribution may have a greater probability that arandom d_(i)=1 than the ideal soliton distribution, which may reduce theprobability of the decoding process failing by increasing theprobability that an encoding symbol is connected to a single sourcesymbol.

The encoding scheme described herein may enable the network entity 305to improve efficiency and reliability of communications with the UEs 315by increasing the probability of successfully decoding source symbolstransmitted in encoding symbols.

FIG. 4 illustrates an example of a process flow 400 that supportsbroadcasting packets using network coding via sidelink with feedback inaccordance with aspects of the present disclosure. In some examples, theprocess flow 400 may implement aspects of wireless communicationssystems 100, 200, and 300. For example, the process flow 400 may includeexample operations associated with one or more of a transmitter 405 or aset of receivers 415, which may be examples of a base station and UEs,respectively, described with reference to FIGS. 1 through 3. Thereceivers 415 may be receivers 415 of a group of receivers 415 thatincludes m receivers 415. In the following description of the processflow 400, the operations between the transmitter 405 and the receivers415 may be performed in a different order than the example order shown,or the operations performed by the transmitter 405 and the receivers 415may be performed in different orders or at different times. Someoperations may also be omitted from the process flow 400, and otheroperations may be added to the process flow 400. The operationsperformed by the transmitter 405 and the receivers 415 may supportimprovement to the transmitter 405 packet transmission operations and,in some examples, may promote improvements to efficiency and reliabilityfor communications between the transmitter 405 and the receivers 415,among other benefits.

At 420, the transmitter 405 may construct a packet pool S={p1,p2, . . .,pn}. The set of network encoded packets may be encoded using a networkencoding function q=f(S)={q1,q2, . . . ,qk} and the set of networkencoded packets q may be transmitted to the receivers 415 (e.g.,receivers 415-a, 415-b and 415-c). In some example, the set of networkencoded packets q may be encoded using an LT code.

At 425, each receiver 415 may broadcast successfully received encodedpackets via sidelink connections with the group of receivers 415. Forexample, the receiver 415-a may successfully receive network encodedpackets q1 and q2 of the set q and broadcast q1 and q2 to the otherreceivers 415. Similarly, the receiver 415-b may successfully receivenetwork encoded packets q2 and q3 and broadcast q2 and q3 to the otherreceivers 415. Likewise, the receiver 415-c may successfully receivenetwork encoded packets q2 and q5 and may broadcast q2 and q5 to theother receivers 415.

At 430, each receiver 415 may gather network encoded packets receivedfrom the direct link and the sidelink connections and send feedback tothe transmitter 405. For example, the receiver 415-a may receive thebroadcast from the receiver 415-b and may thus have received a firstsubset of network encoded packets {q1, q2, q3}. The receiver 415-a maytransmit feedback to the transmitter 405 indicating that the receiver415-a has received the first subset. Similarly, the receiver 415-b mayreceive the broadcast from receiver 415-c and may thus have received asecond subset of network encoded packets {q2, q3, q5}. The receiver415-b may transmit feedback to the transmitter 405 indicating that thereceiver 415-b has received the second subset. Likewise, the receiver415-c may receive the broadcast from receiver 415-a and may thus havereceived a third subset of network encoded packets {q1, q2, q5}.Receiver 415-c may transmit feedback to transmitter 405 indicating thatreceiver 415-c has received the third subset.

At 435, transmitter 405 may calculate a set of received network encodedpackets M. In one example, M may represent the union of the subsets ofreceived network encoded packets identified in the feedback; that is,M={q1,q2,q2}∪{q2,q3,q5}∪{q1,q2,q5}={q1,q2,q3,q5}. Alternatively, M mayrepresent the intersection of the subsets of received network encodedpackets identified in the feedback; that is,M={q1,q2,q3}∩{q2,q3,q5}∩{q1,q2,q5}={q2}. In some examples, thetransmitter 405 may additionally calculate the respective subset ofreceived network encoded packets Mi for each receiver 415 (e.g., thefirst, second, and third subsets) and decode the subsets Mi using thesame decoding algorithm as the receivers 415 to infer which packets ofthe set of packets were recovered at each receiver 415.

At 440, transmitter 405 may generate newly encoded packets using thepacket pool S and transmit network encoded packets that do not containM. For instance, the transmitter 405 may determine a set of networkencoded packets according to f(S). The transmitter 405 may determine thenewly encoded packets according to f(S)-M. If M is the union of thesubsets of received network encoded packets identified in the feedbackat 430, the set of encoded packets transmitted to the receivers 415 maybe {q1,q2, . . . ,qk}−{q1,q2,q3,q5}={q4, . . . ,qk}. Alternatively, if Mis the intersection of the subsets of received network encoded packetsidentified in the feedback at 430, the updated set of network encodedpackets transmitted to the receivers 415 may be {q1,q2, . . .,qk}−{q2}={q1,q3, . . . ,qk}.

At 445, the transmitter 405 and the receivers 415 may continue toperform the operations described at 425 through 440 until thetransmitter 405 infers all packets of the packet pool S have beensuccessfully recovered by all receivers 415.

FIG. 5 illustrates an example of a process flow 500 that supportsbroadcasting packets using network coding via sidelink with feedback inaccordance with aspects of the present disclosure. In some examples, theprocess flow 500 may implement aspects of wireless communicationssystems 100, 200, and 300. For example, the process flow 500 may includeexample operations associated with one or more of a network entity 505or a set of one or more UEs 515, which may be examples of thecorresponding devices described with reference to FIGS. 1 through 3. Inthe following description of the process flow 500, the operationsbetween the network entity 505 and the UEs 515 may be performed in adifferent order than the example order shown, or the operationsperformed by the network entity 505 and the UEs 515 may be performed indifferent orders or at different times. Some operations may also beomitted from the process flow 500, and other operations may be added tothe process flow 500. The operations performed by the network entity 505and the UEs 515 may support improvement to the network entity 505 packettransmission operations and, in some examples, may promote improvementsto efficiency and reliability for communications between the networkentity 505 and the UEs 515, among other benefits.

At 520, the network entity 505 may identify a set of one or more packetsfor transmission to the UEs 515. In one example, the network entity 505identifies the set of one or more packets from a packet pool, which maybe a set of one or more packets scheduled for broadcasting. In someexamples, the broadcasting may support a content streaming service andthe packets may correspond to the streamed content. From the set of oneor more packets, the network entity 505 may encode (e.g., using LTcoding) a set of one or more network encoded packets.

At 525, the network entity 505 may broadcast the set of one or morenetwork encoded packets to the UEs 515. Each of the UEs 515 may receiveone or more network encoded packets of the set of one or more networkencoded packets. For example, some network encoded packets may be lostbased on a transmission environment. At 530, each UE 515 may broadcastsuccessfully received encoded packets via sidelink connections with thegroup of UEs 515.

At 535, each UE 515 may gather network encoded packets received from thedirect link and the sidelink connections to determine a respectivesubset of one or more successfully received network encoded packets. At540, the UEs 515 may each transmit feedback to the network entity 505indicating the respective subset of one or more successfully receivednetwork encoded packets. As noted herein, the feedback may be an exampleof one or more HARQ messages. In other cases, the feedback may be anexample of a PDCP status report or RLC status report. In some examples,the UEs 515 may transmit the feedback in the network coding sub-layer,and such feedback may directly indicate the receiving success/failurecorresponding to each packet. In some cases, one or more of the UEs 515may transmit a CSI report to facilitate MCS selection or rate control.In some examples, the CSI report is transmitted when a NACK istransmitted in order to request the updated MCS or data encoding ratefor better data reception.

In some examples, the UEs 515 may decode the one or more successfullyreceived network encoded packets concurrent with transmitting thefeedback. As noted herein, one or more sets of network coding parametersmay be configured at the UEs 515 (e.g., via MAC-CE or DCI). In somecases, one or more UEs 515 may request (e.g., along with transmittingthe feedback) an updated set of one or more network coding parameters(e.g., via MAC-CE or UCI).

At 545, the network entity 505 may determine a subset of one or moresuccessfully received network encoded packets based on the feedback. Inone example, the subset may represent one or more successfully receivedpackets included in each of the subsets (e.g., an intersection of thesubsets). In another example, the subset may represent one or moresuccessfully received packets included in any of the subsets (e.g., aunion of the subsets). In some examples, the network entity 505 mayadditionally calculate the respective subset of received network encodedpackets for each UE 515 and decode the subsets using the same decodingalgorithm as the UEs 515 to infer which packets of the set of one ormore packets were recovered at each UE 515. At 550, the network entity505 may generate newly encoded packets, for example using the packetpool.

At 555, the network entity may transmit an updated set of one or morenetwork encoded packets based on generating the newly encoded packets.The updated set of one or more network encoded packets may not containthe subset of one or more successfully received network encoded packetsdetermined based on the feedback (e.g., the union or the intersection ofthe subsets indicated in the feedback).

At 560, the network entity 505 and the UEs 515 may continue to performthe operations described at 530 through 555 until the network entity 505infers all packets of the packet pool have been successfully recoveredby all receiver UEs 515 (e.g., based on decoding the one or moresuccessfully received network encoded packets indicated in thefeedback). The operations performed by the network entity 505 and theUEs 515 may support improvements to the network entity 505 packettransmission operations and, in some examples, may promote improvementsto efficiency and reliability for communications between the networkentity 505 and the UEs 515, among other benefits.

FIG. 6 shows a block diagram 600 of a device 605 that supportsbroadcasting packets using network coding via sidelink with feedback inaccordance with aspects of the present disclosure. The device 605 may bean example of aspects of a base station 105 as described herein. Thedevice 605 may include a receiver 610, a communications manager 615, anda transmitter 620. The device 605 may also include a processor. Each ofthese components may be in communication with one another (e.g., via oneor more buses).

The receiver 610 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to broadcastingpackets using network coding via sidelink with feedback, etc.).Information may be passed on to other components of the device 605. Thereceiver 610 may be an example of aspects of the transceiver 920described with reference to FIG. 9. The receiver 610 may utilize asingle antenna or a set of one or more antennas.

The communications manager 615 may transmit, to a plurality of UEs, aset of one or more network encoded packets representing a set of one ormore packets identified for broadcast to the plurality of UEs, receivefeedback from each of one or more of the plurality of UEs, the feedbackindicating, as respective subsets of the set of one or more networkencoded packets, one or more successfully received network encodedpackets of the set of one or more network encoded packets at each of theone or more UEs, determine, based on the feedback indicative of the oneor more successfully received network encoded packets, a subset of theset of one or more network encoded packets that was successfullyreceived for each of the one or more of the plurality of UEs providingthe feedback, generate, based on the feedback, an updated set of one ormore network encoded packets based on the set of one or more packets,where the updated set of one or more network encoded packets excludesthe subset of the set of one or more network encoded packets that wassuccessfully received, and transmit the updated set of one or morenetwork encoded packets to the plurality of UEs.

The communications manager 615 as described herein may be implemented torealize one or more potential advantages. One implementation may allowthe device 605 to save power by communicating with UEs 115 (as shown inFIG. 1) more efficiently. For example, the device 605 may improvereliability in communications with UEs 115, as the device 605 may beable to determine, based on receiving feedback, which broadcast packetswere successfully received at the UEs 115. Using the techniquesdescribed herein, the device 605 may reduce waste and duplication ofpackets by retransmitting packets that have not been received by the UEs115. The communications manager 615 may be an example of aspects of thecommunications manager 910 described herein.

The communications manager 615, or its sub-components, may beimplemented in hardware, code (e.g., software or firmware) executed by aprocessor, or any combination thereof. If implemented in code executedby a processor, the functions of the communications manager 615, or itssub-components may be executed by a general-purpose processor, a digitalsignal processor (DSP), an application-specific integrated circuit(ASIC), a field-programmable gate array (FPGA) or other programmablelogic device, discrete gate or transistor logic, discrete hardwarecomponents, or any combination thereof designed to perform the functionsdescribed in the present disclosure.

The communications manager 615, or its sub-components, may be physicallylocated at various positions, including being distributed such thatportions of functions are implemented at different physical locations byone or more physical components. In some examples, the communicationsmanager 615, or its sub-components, may be a separate and distinctcomponent in accordance with various aspects of the present disclosure.In some examples, the communications manager 615, or its sub-components,may be combined with one or more other hardware components, includingbut not limited to an input/output (I/O) component, a transceiver, anetwork server, another computing device, one or more other componentsdescribed in the present disclosure, or a combination thereof inaccordance with various aspects of the present disclosure.

The transmitter 620 may transmit signals generated by other componentsof the device 605. In some examples, the transmitter 620 may becollocated with a receiver 610 in a transceiver module. For example, thetransmitter 620 may be an example of aspects of the transceiver 920described with reference to FIG. 9. The transmitter 620 may utilize asingle antenna or a set of one or more antennas.

By including or configuring the communications manager 615 in accordancewith examples as described herein, the device 605 (e.g., a processorcontrolling or otherwise coupled to the receiver 610, the transmitter620, the communications manager 615, or a combination thereof) maysupport techniques for reduced processing, reduced power consumption,and more efficient utilization of communication resources.

FIG. 7 shows a block diagram 700 of a device 705 that supportsbroadcasting packets using network coding via sidelink with feedback inaccordance with aspects of the present disclosure. The device 705 may bean example of aspects of a device 605, or a base station 105 asdescribed herein. The device 705 may include a receiver 710, acommunications manager 715, and a transmitter 740. The device 705 mayalso include a processor. Each of these components may be incommunication with one another (e.g., via one or more buses).

The receiver 710 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to broadcastingpackets using network coding via sidelink with feedback, etc.).Information may be passed on to other components of the device 705. Thereceiver 710 may be an example of aspects of the transceiver 920described with reference to FIG. 9. The receiver 710 may utilize asingle antenna or a set of one or more antennas.

The communications manager 715 may be an example of aspects of thecommunications manager 615 as described herein. The communicationsmanager 715 may include a packet transmission manager 720, a feedbackmanager 725, a received packet identifier 730, and a packet encodingmanager 735. The communications manager 715 may be an example of aspectsof the communications manager 910 described herein.

The packet transmission manager 720 may transmit, to a plurality of UEs,a set of one or more network encoded packets representing a set of oneor more packets identified for broadcast to the plurality of UEs.

The feedback manager 725 may receive feedback from each of one or moreof the plurality of UEs, the feedback indicating, as respective subsetsof the set of one or more network encoded packets, one or moresuccessfully received network encoded packets of the set of one or morenetwork encoded packets at each of the one or more UEs.

The received packet identifier 730 may determine, based on the feedbackindicative of the one or more successfully received network encodedpackets, a subset of the set of one or more network encoded packets thatwas successfully received for each of the one or more of the pluralityof UEs providing the feedback.

The packet encoding manager 735 may generate, based on the feedback, anupdated set of one or more network encoded packets based on the set ofone or more packets, where the updated set of one or more networkencoded packets excludes the subset of the set of one or more networkencoded packets that was successfully received.

The packet transmission manager 720 may transmit the updated set of oneor more network encoded packets to the plurality of UEs

The transmitter 740 may transmit signals generated by other componentsof the device 705. In some examples, the transmitter 740 may becollocated with a receiver 710 in a transceiver module. For example, thetransmitter 740 may be an example of aspects of the transceiver 920described with reference to FIG. 9. The transmitter 740 may utilize asingle antenna or a set of one or more antennas.

FIG. 8 shows a block diagram 800 of a communications manager 805 thatsupports broadcasting packets using network coding via sidelink withfeedback in accordance with aspects of the present disclosure. Thecommunications manager 805 may be an example of aspects of acommunications manager 615, a communications manager 715, or acommunications manager 910 described herein. The communications manager805 may include a packet transmission manager 810, a feedback manager815, a received packet identifier 820, a packet encoding manager 825, adecoder 830, and a coding parameter manager 835. Each of these modulesmay communicate, directly or indirectly, with one another (e.g., via oneor more buses).

The packet transmission manager 810 may transmit, to a plurality of UEs,a set of one or more network encoded packets representing a set of oneor more packets identified for broadcast to the plurality of UEs.

In some examples, the packet transmission manager 810 may transmit theupdated set of one or more network encoded packets to the plurality ofUEs.

In some examples, the packet transmission manager 810 may identify theset of one or more packets from a packet pool scheduled for broadcast tothe plurality of UEs.

In some examples, the packet transmission manager 810 may identify oneor more additional packets for broadcast to the plurality of UEs basedon the one or more additional packets being added to the packet pool.

The feedback manager 815 may receive feedback from each of one or moreof the plurality of UEs, the feedback indicating, as respective subsetsof the set of one or more network encoded packets, one or moresuccessfully received network encoded packets of the set of one or morenetwork encoded packets at each of the one or more UEs.

In some examples, the feedback manager 815 may receive the feedback viaa packet data convergence protocol (PDCP) status report, an RLC statusreport, or a HARQ message.

In some examples, the feedback manager 815 may receive the feedback in anetwork coding sub-layer, where the feedback indicates a decoding statusof each packet of the set of one or more packets.

In some examples, the feedback manager 815 may receive a channel stateinformation message in conjunction with the feedback.

In some examples, the feedback manager 815 may receive the channel stateinformation message based on the feedback indicating a negativeacknowledgement for one or more of the set of one or more networkencoded packets.

The received packet identifier 820 may determine, based on the feedbackindicative of the one or more successfully received network encodedpackets, a subset of the set of one or more network encoded packets thatwas successfully received for each of the one or more of the pluralityof UEs providing the feedback.

In some examples, the received packet identifier 820 may determine anintersection of each of the subsets indicated in the feedback toidentify the one or more successfully received packets included in eachof the subsets.

In some examples, the received packet identifier 820 may determine,based on the feedback indicative of the one or more successfullyreceived network encoded packets, a second subset of the set of one ormore network encoded packets that was successfully received at any ofthe one or more of the plurality of UEs providing the feedback, wherethe updated set of one or more network encoded packets further excludesthe second subset of the set of one or more network encoded packets.

In some examples, the received packet identifier 820 may determine aunion of each of the subsets indicated in the feedback to identify theone or more successfully received packets included in each of thesubsets.

The packet encoding manager 825 may generate, based on the feedback, anupdated set of one or more network encoded packets based on the set ofone or more packets, where the updated set of one or more networkencoded packets excludes the subset of the set of one or more networkencoded packets that was successfully received.

In some examples, the packet encoding manager 825 may continue to updateand transmit the updated set of one or more network encoded packetsbased on additional feedback received from the one or more of theplurality of UEs until the network node determines that each UE of theplurality of UEs has recovered the set of one or more packets.

In some examples, the packet encoding manager 825 may determine one ormore encoding metrics for transmission of the updated set of one or morepackets based on the channel state information message.

In some examples, the packet encoding manager 825 may determine amodulation and coding scheme, an encoding rate, or both.

In some examples, the packet encoding manager 825 may encode the set ofone or more network encoded packets according to a Luby transform (LT)code, where each network encoded packet of the set of one or morenetwork encoded packets is constructed from one or more packets of theset of one or more packets identified for broadcast to the plurality ofUEs according to a distribution.

In some cases, the distribution includes an ideal soliton distribution,a robust soliton distribution, or any combination thereof.

The decoder 830 may decode the one or more successfully received packetsincluded in each of the subsets indicated in the feedback and theadditional feedback, where the network node determines that each UE ofthe plurality of UEs has recovered the set of one or more packets basedon the decoding.

The coding parameter manager 835 may transmit, to one or more of theplurality of UEs, an indication of one or more network codingparameters, where at least the updated set of one or more networkencoded packets are transmitted to the plurality of UEs in accordancewith the one or more network coding parameters.

In some examples, the coding parameter manager 835 may transmit anindication of a network coding algorithm, a network encoding function, anetwork encoding matrix, a number of decoding iterations, or anycombination thereof.

In some examples, the coding parameter manager 835 may transmit the oneor more network coding parameters using medium access control-controlelement (MAC-CE) signaling, downlink control information signaling,radio resource control signaling, or any combination thereof.

In some examples, the coding parameter manager 835 may transmit anindication to switch from one or more prior network coding parameters tothe one or more network coding parameters.

In some examples, the coding parameter manager 835 may receive, from theone or more of the plurality of UEs, a request for the one or morenetwork coding parameters, where the indication of the one or morenetwork coding parameters is transmitted based on receiving the request.

In some examples, the coding parameter manager 835 may receive, therequest using medium access control-control element (MAC-CE) signalingor uplink control information signaling.

FIG. 9 shows a diagram of a system 900 including a device 905 thatsupports broadcasting packets using network coding via sidelink withfeedback in accordance with aspects of the present disclosure. Thedevice 905 may be an example of or include the components of device 605,device 705, or a base station 105 as described herein. The device 905may include components for bi-directional voice and data communicationsincluding components for transmitting and receiving communications,including a communications manager 910, a network communications manager915, a transceiver 920, an antenna 925, memory 930, a processor 940, andan inter-station communications manager 945. These components may be inelectronic communication via one or more buses (e.g., bus 950).

The communications manager 910 may transmit, to a plurality of UEs, aset of one or more network encoded packets representing a set of one ormore packets identified for broadcast to the plurality of UEs, receivefeedback from each of one or more of the plurality of UEs, the feedbackindicating, as respective subsets of the set of one or more networkencoded packets, one or more successfully received network encodedpackets of the set of one or more network encoded packets at each of theone or more UEs, determine, based on the feedback indicative of the oneor more successfully received network encoded packets, a subset of theset of one or more network encoded packets that was successfullyreceived for each of the one or more of the plurality of UEs providingthe feedback, generate, based on the feedback, an updated set of one ormore network encoded packets based on the set of one or more packets,where the updated set of one or more network encoded packets excludesthe subset of the set of one or more network encoded packets that wassuccessfully received, and transmit the updated set of one or morenetwork encoded packets to the plurality of UEs.

The network communications manager 915 may manage communications withthe core network (e.g., via one or more wired backhaul links). Forexample, the network communications manager 915 may manage the transferof data communications for client devices, such as one or more UEs 115.

The transceiver 920 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described above. For example, thetransceiver 920 may represent a wireless transceiver and may communicatebi-directionally with another wireless transceiver. The transceiver 920may also include a modem to modulate the packets and provide themodulated packets to the antennas for transmission, and to demodulatepackets received from the antennas.

In some cases, the wireless device may include a single antenna 925.However, in some cases the device may have more than one antenna 925,which may be capable of concurrently transmitting or receiving multiplewireless transmissions.

The memory 930 may include random-access memory (RAM), read-only memory(ROM), or a combination thereof. The memory 930 may storecomputer-readable code 935 including instructions that, when executed bya processor (e.g., the processor 940) cause the device to performvarious functions described herein. In some cases, the memory 930 maycontain, among other things, a basic input/output system (BIOS) whichmay control basic hardware or software operation such as the interactionwith peripheral components or devices.

The processor 940 may include an intelligent hardware device (e.g., ageneral-purpose processor, a DSP, a central processing unit (CPU), amicrocontroller, an ASIC, an FPGA, a programmable logic device, adiscrete gate or transistor logic component, a discrete hardwarecomponent, or any combination thereof). In some cases, the processor 940may be configured to operate a memory array using a memory controller.In some cases, a memory controller may be integrated into processor 940.The processor 940 may be configured to execute computer-readableinstructions stored in a memory (e.g., the memory 930) to cause thedevice 905 to perform various functions (e.g., functions or taskssupporting broadcasting packets using network coding via sidelink withfeedback).

The processor 940 of the device 905 (e.g., controlling the receiver 610,the transmitter 620, or the transceiver 920) may reduce powerconsumption and increase packet transmission reliability according tothe techniques described herein. In some examples, the processor 940 ofthe device 905 may reconfigure packet transmission operations based onthe received feedback. For example, the processor 940 of the device 905may turn on one or more processing units for configuring the packettransmissions, increase a processing clock, or a similar mechanismwithin the device 905. As such, when subsequent feedback is received,the processor 940 may be ready to respond more efficiently through thereduction of a ramp up in processing power. The improvements in powersaving and packet transmission reliability may further increase powerefficiency at the device 905 (for example, by eliminating unnecessaryrepeated packet transmissions, etc.).

The inter-station communications manager 945 may manage communicationswith other base station 105, and may include a controller or schedulerfor controlling communications with UEs 115 in cooperation with otherbase stations 105. For example, the inter-station communications manager945 may coordinate scheduling for transmissions to UEs 115 for variousinterference mitigation techniques such as beamforming or jointtransmission. In some examples, the inter-station communications manager945 may provide an X2 interface within an LTE/LTE-A wirelesscommunication network technology to provide communication between basestations 105.

The code 935 may include instructions to implement aspects of thepresent disclosure, including instructions to support wirelesscommunications. The code 935 may be stored in a non-transitorycomputer-readable medium such as system memory or other type of memory.In some cases, the code 935 may not be directly executable by theprocessor 940 but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

By including or configuring the communications manager 910 in accordancewith examples as described herein, the device 905 may support techniquesfor improved communication reliability, reduced latency, improved userexperience related to reduced processing, reduced power consumption,more efficient utilization of communication resources, improvedcoordination between devices, longer battery life, and improvedutilization of processing capability.

FIG. 10 shows a flowchart illustrating a method 1000 that supportsbroadcasting packets using network coding via sidelink with feedback inaccordance with aspects of the present disclosure. The operations ofmethod 1000 may be implemented by a base station 105 or its componentsas described herein. For example, the operations of method 1000 may beperformed by a communications manager as described with reference toFIGS. 6 through 9. In some examples, a base station may execute a set ofone or more instructions to control the functional elements of the basestation to perform the functions described below. Additionally oralternatively, a base station may perform aspects of the functionsdescribed below using special-purpose hardware.

At 1005, the base station may transmit, to a plurality of UEs, a set ofone or more network encoded packets representing a set of one or morepackets identified for broadcast to the plurality of UEs. The operationsof 1005 may be performed according to the methods described herein. Insome examples, aspects of the operations of 1005 may be performed by apacket transmission manager as described with reference to FIGS. 6through 9.

At 1010, the base station may receive feedback from each of one or moreof the plurality of UEs, the feedback indicating, as respective subsetsof the set of one or more network encoded packets, one or moresuccessfully received network encoded packets of the set of one or morenetwork encoded packets at each of the one or more UEs. The operationsof 1010 may be performed according to the methods described herein. Insome examples, aspects of the operations of 1010 may be performed by afeedback manager as described with reference to FIGS. 6 through 9.

At 1015, the base station may determine, based on the feedbackindicative of the one or more successfully received network encodedpackets, a subset of the set of one or more network encoded packets thatwas successfully received for each of the one or more of the pluralityof UEs providing the feedback. The operations of 1015 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1015 may be performed by a received packet identifieras described with reference to FIGS. 6 through 9.

At 1020, the base station may generate, based on the feedback, anupdated set of one or more network encoded packets based on the set ofone or more packets, where the updated set of one or more networkencoded packets excludes the subset of the set of one or more networkencoded packets that was successfully received. The operations of 1020may be performed according to the methods described herein. In someexamples, aspects of the operations of 1020 may be performed by a packetencoding manager as described with reference to FIGS. 6 through 9.

At 1025, the base station may transmit the updated set of one or morenetwork encoded packets to the plurality of UEs. The operations of 1025may be performed according to the methods described herein. In someexamples, aspects of the operations of 1025 may be performed by a packettransmission manager as described with reference to FIGS. 6 through 9.

FIG. 11 shows a flowchart illustrating a method 1100 that supportsbroadcasting packets using network coding via sidelink with feedback inaccordance with aspects of the present disclosure. The operations ofmethod 1100 may be implemented by a base station 105 or its componentsas described herein. For example, the operations of method 1100 may beperformed by a communications manager as described with reference toFIGS. 6 through 9. In some examples, a base station may execute a set ofone or more instructions to control the functional elements of the basestation to perform the functions described below. Additionally oralternatively, a base station may perform aspects of the functionsdescribed below using special-purpose hardware.

At 1105, the base station may transmit, to a plurality of UEs, a set ofone or more network encoded packets representing a set of one or morepackets identified for broadcast to the plurality of UEs. The operationsof 1105 may be performed according to the methods described herein. Insome examples, aspects of the operations of 1105 may be performed by apacket transmission manager as described with reference to FIGS. 6through 9.

At 1110, the base station may receive feedback from each of one or moreof the plurality of UEs, the feedback indicating, as respective subsetsof the set of one or more network encoded packets, one or moresuccessfully received network encoded packets of the set of one or morenetwork encoded packets at each of the one or more UEs. The operationsof 1110 may be performed according to the methods described herein. Insome examples, aspects of the operations of 1110 may be performed by afeedback manager as described with reference to FIGS. 6 through 9.

At 1115, the base station may determine, based on the feedbackindicative of the one or more successfully received network encodedpackets, a subset of the set of one or more network encoded packets thatwas successfully received for each of the one or more of the pluralityof UEs providing the feedback. The operations of 1115 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1115 may be performed by a received packet identifieras described with reference to FIGS. 6 through 9.

At 1120, the base station may decode the one or more successfullyreceived packets included in each of the subsets indicated in thefeedback and the additional feedback. The operations of 1120 may beperformed according to the methods described herein. In some examples,aspects of the operations of 1120 may be performed by a decoder asdescribed with reference to FIGS. 6 through 9.

At 1125, the base station may generate, based on the feedback, anupdated set of one or more network encoded packets based on the set ofone or more packets, where the updated set of one or more networkencoded packets excludes the subset of the set of one or more networkencoded packets that was successfully received. The operations of 1125may be performed according to the methods described herein. In someexamples, aspects of the operations of 1125 may be performed by a packetencoding manager as described with reference to FIGS. 6 through 9.

At 1130, the base station may transmit the updated set of one or morenetwork encoded packets to the plurality of UEs. The operations of 1130may be performed according to the methods described herein. In someexamples, aspects of the operations of 1130 may be performed by a packettransmission manager as described with reference to FIGS. 6 through 9.

At 1135, the base station may continue to update and transmit theupdated set of one or more network encoded packets based on additionalfeedback received from the one or more of the plurality of UEs until thenetwork node determines that each UE of the plurality of UEs hasrecovered the set of one or more packets based on the decoding. Theoperations of 1135 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1135 may beperformed by a packet encoding manager as described with reference toFIGS. 6 through 9.

It should be noted that the methods described herein describe possibleimplementations, and that the operations and the steps may be rearrangedor otherwise modified and that other implementations are possible.Further, aspects from two or more of the methods may be combined.

The following provides an overview of aspects of the present disclosure:

Aspect 1: A method for wireless communication at a network node,comprising: transmitting, to a plurality of UEs, a set of one or morenetwork encoded packets representing a set of one or more packetsidentified for broadcast to the plurality of UEs; receiving feedbackfrom each of one or more of the plurality of UEs, the feedbackindicating, as respective subsets of the set of one or more networkencoded packets, one or more successfully received network encodedpackets of the set of one or more network encoded packets at each of theone or more UEs; determining, based at least in part on the feedbackindicative of the one or more successfully received network encodedpackets, a subset of the set of one or more network encoded packets thatwas successfully received for each of the one or more of the pluralityof UEs providing the feedback; generating, based at least in part on thefeedback, an updated set of one or more network encoded packets based atleast in part on the set of one or more packets, wherein the updated setof one or more network encoded packets excludes the subset of the set ofone or more network encoded packets that was successfully received; andtransmitting the updated set of one or more network encoded packets tothe plurality of UEs.

Aspect 2: The method of aspect 1, further comprising: continuing toupdate and transmit the updated set of one or more network encodedpackets based on additional feedback received from the one or more ofthe plurality of UEs until the network node determines that each UE ofthe plurality of UEs has recovered the set of one or more packets.

Aspect 3: The method of aspect 2, further comprising: decoding the oneor more successfully received packets included in each of the subsetsindicated in the feedback and the additional feedback, wherein thenetwork node determines that each UE of the plurality of UEs hasrecovered the set of one or more packets based at least in part on thedecoding.

Aspect 4: The method of any of aspects 1 through 3, wherein determiningthe subset of the set of one or more network encoded packets comprises:determining an intersection of each of the subsets indicated in thefeedback to identify the one or more successfully received packetsincluded in each of the subsets.

Aspect 5: The method of any of aspects 1 through 4, further comprising:determining, based at least in part on the feedback indicative of theone or more successfully received network encoded packets, a secondsubset of the set of one or more network encoded packets that wassuccessfully received at any of the one or more of the plurality of UEsproviding the feedback, wherein the updated set of one or more networkencoded packets further excludes the second subset of the set of one ormore network encoded packets.

Aspect 6: The method of aspect 5, wherein determining the second subsetof the set of one or more network encoded packets comprises: determininga union of each of the subsets indicated in the feedback to identify theone or more successfully received packets included in each of thesubsets.

Aspect 7: The method of any of aspects 1 through 6, wherein receivingthe feedback comprises: receiving the feedback via a packet dataconvergence protocol (PDCP) status report, an RLC status report, or anHARQ message.

Aspect 8: The method of any of aspects 1 through 7, wherein receivingthe feedback comprises: receiving the feedback in a network codingsub-layer, wherein the feedback indicates a decoding status of eachpacket of the set of one or more packets.

Aspect 9: The method of any of aspects 1 through 8, further comprising:receiving a channel state information message in conjunction with thefeedback; and determining one or more encoding metrics for transmissionof the updated set of one or more packets based at least in part on thechannel state information message.

Aspect 10: The method of aspect 9, wherein determining the one or moreencoding metrics comprises: determining a modulation and coding scheme,an encoding rate, or both.

Aspect 11: The method of any of aspects 9 through 10, wherein receivingthe channel state information message comprises: receiving the channelstate information message based at least in part on the feedbackindicating a negative acknowledgement for one or more of the set of oneor more network encoded packets.

Aspect 12: The method of any of aspects 1 through 11, furthercomprising: transmitting, to one or more of the plurality of UEs, anindication of one or more network coding parameters, wherein at leastthe updated set of one or more network encoded packets are transmittedto the plurality of UEs in accordance with the one or more networkcoding parameters.

Aspect 13: The method of aspect 12, wherein transmitting the indicationof the one or more network coding parameters comprises: transmitting anindication of a network coding algorithm, a network encoding function, anetwork encoding matrix, a number of decoding iterations, or anycombination thereof.

Aspect 14: The method of any of aspects 12 through 13, whereintransmitting the indication of the one or more network coding parameterscomprises: transmitting the one or more network coding parameters usingmedium access control-control element (MAC-CE) signaling, downlinkcontrol information signaling, radio resource control signaling, or anycombination thereof.

Aspect 15: The method of any of aspects 12 through 14, whereintransmitting the indication of the one or more network coding parameterscomprises: transmitting an indication to switch from one or more priornetwork coding parameters to the one or more network coding parameters.

Aspect 16: The method of any of aspects 12 through 15, furthercomprising: receiving, from the one or more of the plurality of UEs, arequest for the one or more network coding parameters, wherein theindication of the one or more network coding parameters is transmittedbased at least in part on receiving the request.

Aspect 17: The method of aspect 16, wherein receiving the requestcomprises: receiving the request using medium access control-controlelement (MAC-CE) signaling or uplink control information signaling.

Aspect 18: The method of any of aspects 1 through 17, furthercomprising: identifying the set of one or more packets from a packetpool scheduled for broadcast to the plurality of UEs.

Aspect 19: The method of aspect 18, further comprising: identifying oneor more additional packets for broadcast to the plurality of UEs basedat least in part on the one or more additional packets being added tothe packet pool.

Aspect 20: The method of any of aspects 1 through 19, furthercomprising: encoding the set of one or more network encoded packetsaccording to a Luby transform (LT) code, wherein each network encodedpacket of the set of one or more network encoded packets is constructedfrom one or more packets of the set of one or more packets identifiedfor broadcast to the plurality of UEs according to a distribution.

Aspect 21: The method of aspect 20, wherein the distribution comprisesan ideal soliton distribution, a robust soliton distribution, or anycombination thereof.

Aspect 22: An apparatus for wireless communication at a network node,comprising a processor; memory coupled with the processor; andinstructions stored in the memory and executable by the processor tocause the apparatus to perform a method of any of aspects 1 through 21.

Aspect 23: An apparatus for wireless communication at a network node,comprising at least one means for performing a method of any of aspects1 through 21.

Aspect 24: A non-transitory computer-readable medium storing code forwireless communication at a network node, the code comprisinginstructions executable by a processor to perform a method of any ofaspects 1 through 21.

Although aspects of an LTE, LTE-A, LTE-A Pro, or NR system may bedescribed for purposes of example, and LTE, LTE-A, LTE-A Pro, or NRterminology may be used in much of the description, the techniquesdescribed herein are applicable beyond LTE, LTE-A, LTE-A Pro, or NRnetworks. For example, the described techniques may be applicable tovarious other wireless communications systems such as Ultra MobileBroadband (UMB), Institute of Electrical and Electronics Engineers(IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM, aswell as other systems and radio technologies not explicitly mentionedherein.

Information and signals described herein may be represented using any ofa variety of different technologies and techniques. For example, data,instructions, commands, information, signals, bits, symbols, and chipsthat may be referenced throughout the description may be represented byvoltages, currents, electromagnetic waves, magnetic fields or particles,optical fields or particles, or any combination thereof.

The various illustrative blocks and components described in connectionwith the disclosure herein may be implemented or performed with ageneral-purpose processor, a DSP, an ASIC, a CPU, an FPGA or otherprogrammable logic device, discrete gate or transistor logic, discretehardware components, or any combination thereof designed to perform thefunctions described herein. A general-purpose processor may be amicroprocessor, but in the alternative, the processor may be anyprocessor, controller, microcontroller, or state machine. A processormay also be implemented as a combination of computing devices (e.g., acombination of a DSP and a microprocessor, multiple microprocessors, oneor more microprocessors in conjunction with a DSP core, or any othersuch configuration).

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope of the disclosure and appended claims. For example, due to thenature of software, functions described herein may be implemented usingsoftware executed by a processor, hardware, firmware, hardwiring, orcombinations of any of these. Features implementing functions may alsobe physically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations.

Computer-readable media includes both non-transitory computer storagemedia and communication media including any medium that facilitatestransfer of a computer program from one place to another. Anon-transitory storage medium may be any available medium that may beaccessed by a general-purpose or special purpose computer. By way ofexample, and not limitation, non-transitory computer-readable media mayinclude RAM, ROM, electrically erasable programmable ROM (EEPROM), flashmemory, compact disk (CD) ROM or other optical disk storage, magneticdisk storage or other magnetic storage devices, or any othernon-transitory medium that may be used to carry or store desired programcode means in the form of instructions or data structures and that maybe accessed by a general-purpose or special-purpose computer, or ageneral-purpose or special-purpose processor. Also, any connection isproperly termed a computer-readable medium. For example, if the softwareis transmitted from a website, server, or other remote source using acoaxial cable, fiber optic cable, twisted pair, digital subscriber line(DSL), or wireless technologies such as infrared, radio, and microwave,then the coaxial cable, fiber optic cable, twisted pair, DSL, orwireless technologies such as infrared, radio, and microwave areincluded in the definition of computer-readable medium. Disk and disc,as used herein, include CD, laser disc, optical disc, digital versatiledisc (DVD), floppy disk and Blu-ray disc where disks usually reproducedata magnetically, while discs reproduce data optically with lasers.Combinations of the above are also included within the scope ofcomputer-readable media.

As used herein, including in the claims, “or” as used in a list of items(e.g., a list of items prefaced by a phrase such as “at least one of” or“one or more of”) indicates an inclusive list such that, for example, alist of at least one of A, B, or C means A or B or C or AB or AC or BCor ABC (i.e., A and B and C). Also, as used herein, the phrase “basedon” shall not be construed as a reference to a closed set of one or moreconditions. For example, an example step that is described as “based oncondition A” may be based on both a condition A and a condition Bwithout departing from the scope of the present disclosure. In otherwords, as used herein, the phrase “based on” shall be construed in thesame manner as the phrase “based at least in part on.”

In the appended figures, similar components or features may have thesame reference label. Further, various components of the same type maybe distinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If just the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label, or othersubsequent reference label.

The description set forth herein, in connection with the appendeddrawings, describes example configurations and does not represent allthe examples that may be implemented or that are within the scope of theclaims. The term “example” used herein means “serving as an example,instance, or illustration,” and not “preferred” or “advantageous overother examples.” The detailed description includes specific details forthe purpose of providing an understanding of the described techniques.These techniques, however, may be practiced without these specificdetails. In some instances, known structures and devices are shown inblock diagram form in order to avoid obscuring the concepts of thedescribed examples.

The description herein is provided to enable a person having ordinaryskill in the art to make or use the disclosure. Various modifications tothe disclosure will be apparent to a person having ordinary skill in theart, and the generic principles defined herein may be applied to othervariations without departing from the scope of the disclosure. Thus, thedisclosure is not limited to the examples and designs described herein,but is to be accorded the broadest scope consistent with the principlesand novel features disclosed herein.

What is claimed is:
 1. A method for wireless communication at a networknode, comprising: transmitting, to a plurality of UEs, a set of one ormore network encoded packets representing a set of one or more packetsidentified for broadcast to the plurality of UEs; receiving feedbackfrom each of one or more of the plurality of UEs, the feedbackindicating, as respective subsets of the set of one or more networkencoded packets, one or more successfully received network encodedpackets of the set of one or more network encoded packets at each of theone or more UEs; determining, based at least in part on the feedbackindicative of the one or more successfully received network encodedpackets, a subset of the set of one or more network encoded packets thatwas successfully received for each of the one or more of the pluralityof UEs providing the feedback; generating, based at least in part on thefeedback, an updated set of one or more network encoded packets based atleast in part on the set of one or more packets, wherein the updated setof one or more network encoded packets excludes the subset of the set ofone or more network encoded packets that was successfully received; andtransmitting the updated set of one or more network encoded packets tothe plurality of UEs.
 2. The method of claim 1, further comprising:continuing to update and transmit the updated set of one or more networkencoded packets based on additional feedback received from the one ormore of the plurality of UEs until the network node determines that eachUE of the plurality of UEs has recovered the set of one or more packets.3. The method of claim 2, further comprising: decoding the one or moresuccessfully received packets included in each of the subsets indicatedin the feedback and the additional feedback, wherein the network nodedetermines that each UE of the plurality of UEs has recovered the set ofone or more packets based at least in part on the decoding.
 4. Themethod of claim 1, wherein determining the subset of the set of one ormore network encoded packets comprises: determining an intersection ofeach of the subsets indicated in the feedback to identify the one ormore successfully received packets included in each of the subsets. 5.The method of claim 1, further comprising: determining, based at leastin part on the feedback indicative of the one or more successfullyreceived network encoded packets, a second subset of the set of one ormore network encoded packets that was successfully received at any ofthe one or more of the plurality of UEs providing the feedback, whereinthe updated set of one or more network encoded packets further excludesthe second subset of the set of one or more network encoded packets. 6.The method of claim 5, wherein determining the second subset of the setof one or more network encoded packets comprises: determining a union ofeach of the subsets indicated in the feedback to identify the one ormore successfully received packets included in each of the subsets. 7.The method of claim 1, wherein receiving the feedback comprises:receiving the feedback via a packet data convergence protocol (PDCP)status report, a radio link control (RLC) status report, or a hybridautomatic repeat request (HARD) message.
 8. The method of claim 1,wherein receiving the feedback comprises: receiving the feedback in anetwork coding sub-layer, wherein the feedback indicates a decodingstatus of each packet of the set of one or more packets.
 9. The methodof claim 1, further comprising: receiving a channel state informationmessage in conjunction with the feedback; and determining one or moreencoding metrics for transmission of the updated set of one or morepackets based at least in part on the channel state information message.10. The method of claim 9, wherein determining the one or more encodingmetrics comprises: determining a modulation and coding scheme, anencoding rate, or both.
 11. The method of claim 9, wherein receiving thechannel state information message comprises: receiving the channel stateinformation message based at least in part on the feedback indicating anegative acknowledgement for one or more of the set of one or morenetwork encoded packets.
 12. The method of claim 1, further comprising:transmitting, to one or more of the plurality of UEs, an indication ofone or more network coding parameters, wherein at least the updated setof one or more network encoded packets are transmitted to the pluralityof UEs in accordance with the one or more network coding parameters. 13.The method of claim 12, wherein transmitting the indication of the oneor more network coding parameters comprises: transmitting an indicationof a network coding algorithm, a network encoding function, a networkencoding matrix, a number of decoding iterations, or any combinationthereof.
 14. The method of claim 12, wherein transmitting the indicationof the one or more network coding parameters comprises: transmitting theone or more network coding parameters using medium accesscontrol-control element (MAC-CE) signaling, downlink control informationsignaling, radio resource control signaling, or any combination thereof.15. The method of claim 12, wherein transmitting the indication of theone or more network coding parameters comprises: transmitting anindication to switch from one or more prior network coding parameters tothe one or more network coding parameters.
 16. The method of claim 12,further comprising: receiving, from the one or more of the plurality ofUEs, a request for the one or more network coding parameters, whereinthe indication of the one or more network coding parameters istransmitted based at least in part on receiving the request.
 17. Themethod of claim 16 wherein receiving the request comprises: receivingthe request using medium access control-control element (MAC-CE)signaling or uplink control information signaling.
 18. The method ofclaim 1, further comprising: identifying the set of one or more packetsfrom a packet pool scheduled for broadcast to the plurality of UEs. 19.The method of claim 18, further comprising: identifying one or moreadditional packets for broadcast to the plurality of UEs based at leastin part on the one or more additional packets being added to the packetpool.
 20. The method of claim 1, further comprising: encoding the set ofone or more network encoded packets according to a Luby transform (LT)code, wherein each network encoded packet of the set of one or morenetwork encoded packets is constructed from one or more packets of theset of one or more packets identified for broadcast to the plurality ofUEs according to a distribution.
 21. The method of claim 20, wherein thedistribution comprises an ideal soliton distribution, a robust solitondistribution, or any combination thereof.
 22. An apparatus for wirelesscommunication at a network node, comprising: a processor, memory coupledwith the processor; and instructions stored in the memory and executableby the processor to cause the apparatus to: transmit, to a plurality ofUEs, a set of one or more network encoded packets representing a set ofone or more packets identified for broadcast to the plurality of UEs;receive feedback from each of one or more of the plurality of UEs, thefeedback indicating, as respective subsets of the set of one or morenetwork encoded packets, one or more successfully received networkencoded packets of the set of one or more network encoded packets ateach of the one or more UEs; determine, based at least in part on thefeedback indicative of the one or more successfully received networkencoded packets, a subset of the set of one or more network encodedpackets that was successfully received for each of the one or more ofthe plurality of UEs providing the feedback; generate, based at least inpart on the feedback, an updated set of one or more network encodedpackets based at least in part on the set of one or more packets,wherein the updated set of one or more network encoded packets excludesthe subset of the set of one or more network encoded packets that wassuccessfully received; and transmit the updated set of one or morenetwork encoded packets to the plurality of UEs.
 23. The apparatus ofclaim 22, wherein the instructions are further executable by theprocessor to cause the apparatus to: continue to update and transmit theupdated set of one or more network encoded packets based on additionalfeedback received from the one or more of the plurality of UEs until thenetwork node determines that each UE of the plurality of UEs hasrecovered the set of one or more packets.
 24. The apparatus of claim 23,wherein the instructions are further executable by the processor tocause the apparatus to: decode the one or more successfully receivedpackets included in each of the subsets indicated in the feedback andthe additional feedback, wherein the network node determines that eachUE of the plurality of UEs has recovered the set of one or more packetsbased at least in part on the decoding.
 25. The apparatus of claim 22,wherein the instructions are further executable by the processor tocause the apparatus to: determine an intersection of each of the subsetsindicated in the feedback to identify the one or more successfullyreceived packets included in each of the subsets.
 26. The apparatus ofclaim 22, wherein the instructions are further executable by theprocessor to cause the apparatus to: determine, based at least in parton the feedback indicative of the one or more successfully receivednetwork encoded packets, a second subset of the set of one or morenetwork encoded packets that was successfully received at any of the oneor more of the plurality of UEs providing the feedback, wherein theupdated set of one or more network encoded packets further excludes thesecond subset of the set of one or more network encoded packets.
 27. Theapparatus of claim 26, wherein the instructions are further executableby the processor to cause the apparatus to: determine a union of each ofthe subsets indicated in the feedback to identify the one or moresuccessfully received packets included in each of the subsets.
 28. Theapparatus of claim 22, wherein the instructions are further executableby the processor to cause the apparatus to: receive the feedback via apacket data convergence protocol (PDCP) status report, a radio linkcontrol (RLC) status report, or a hybrid automatic repeat request (HARD)message.
 29. An apparatus for wireless communication at a network node,comprising: means for transmitting, to a plurality of UEs, a set of oneor more network encoded packets representing a set of one or morepackets identified for broadcast to the plurality of UEs; means forreceiving feedback from each of one or more of the plurality of UEs, thefeedback indicating, as respective subsets of the set of one or morenetwork encoded packets, one or more successfully received networkencoded packets of the set of one or more network encoded packets ateach of the one or more UEs; means for determining, based at least inpart on the feedback indicative of the one or more successfully receivednetwork encoded packets, a subset of the set of one or more networkencoded packets that was successfully received for each of the one ormore of the plurality of UEs providing the feedback; means forgenerating, based at least in part on the feedback, an updated set ofone or more network encoded packets based at least in part on the set ofone or more packets, wherein the updated set of one or more networkencoded packets excludes the subset of the set of one or more networkencoded packets that was successfully received; and means fortransmitting the updated set of one or more network encoded packets tothe plurality of UEs.
 30. A non-transitory computer-readable mediumstoring code for wireless communication at a network node, the codecomprising instructions executable by a processor to: transmit, to aplurality of UEs, a set of one or more network encoded packetsrepresenting a set of one or more packets identified for broadcast tothe plurality of UEs; receive feedback from each of one or more of theplurality of UEs, the feedback indicating, as respective subsets of theset of one or more network encoded packets, one or more successfullyreceived network encoded packets of the set of one or more networkencoded packets at each of the one or more UEs; determine, based atleast in part on the feedback indicative of the one or more successfullyreceived network encoded packets, a subset of the set of one or morenetwork encoded packets that was successfully received for each of theone or more of the plurality of UEs providing the feedback; generate,based at least in part on the feedback, an updated set of one or morenetwork encoded packets based at least in part on the set of one or morepackets, wherein the updated set of one or more network encoded packetsexcludes the subset of the set of one or more network encoded packetsthat was successfully received; and transmit the updated set of one ormore network encoded packets to the plurality of UEs.